Importance of Good Engineering Practices

Staff: Mentor

I don't know how many heard about this - but this is an example of the importance of good engineering practice - or rather what happens when good engineering oversight is lacking and poor or questionable construction (manufacturing) practices are allowed.

I agree. It will be interesting to watch the fall out. I wouldn't want to be the Registered Engineer whose stamp and signiture is on the design. It is his/her fault if the materials and workmanship are to specifications. But, you don't know if it is the engineer's fault. This is a huge mess and the whole bunch of them, engineer, inspectors and testers should be investigated.

Staff: Mentor

Attorney General Thomas F. Reilly yesterday appealed to Bechtel/Parsons Brinckerhoff, the biggest contractor on the Big Dig, to negotiate a settlement with his office for shoddy work on the $14.6 billion tunnel project, but Bechtel/Parsons Brinckerhoff yesterday showed no indication of moving toward a quick resolution.

''The ball is in their court,'' Reilly said, three days after his office announced its claim for a $108 million refund from Bechtel/Parsons Brinckerhoff and about a dozen smaller design firms supervised by Bechtel/Parsons Brinckerhoff.

That was before the collapse of the panel that killed a woman.

It should have been design properly and constructed properly. There is no excuse for sloppiness - especially when the safety of the public is at stake.

Staff: Mentor

civil_dude said:

I agree. It will be interesting to watch the fall out. I wouldn't want to be the Registered Engineer whose stamp and signiture is on the design. It is his/her fault if the materials and workmanship are to specifications. But, you don't know if it is the engineer's fault. This is a huge mess and the whole bunch of them, engineer, inspectors and testers should be investigated.

Public safety should come first, DAMN the costs, politics and delays.

The way the lawyers see it, the materials used were not up to spec, so to me, this isn't an engineering issue, but a construction oversight issue.

Staff: Mentor

There will always be people willing to gamble with peoples lives on both sides to beat out someone else's bid or come in under budget. You can see it everyday on the freeways, some jackass darting in and out of traffic trying to get home 2 mins sooner then he could if he just cruised along with the rest of us. He's gambling that his reckless actions won't cost him his own life or the life of someone else. It's really sick, but I doubt it will change soon. I used to get really offended at the amount of money people try and sue for in cases like this, but now I see that money is the only language these people understand, so hit them where it hurts.

I always loved that line from Armageddon,

You know we're sitting on four million pounds of fuel, one nuclear weapon and a thing that has 270,000 moving parts built by the lowest bidder

Apply a similar quote to that highway system and your talking about a scary situation.

Staff: Mentor

Civil engineers said the questions must go beyond the quality of workmanship to the tunnel's design: Why were the concrete panels so heavy, weighing 2 1/2 to 3 tons apiece? Why were they there at all, since there was already a higher tunnel roof? And why did the failure of a single steel hanger send six to 10 of the slabs crashing down?

Initial reports from eyewitnesses and investigators indicate the accident began with a loud snap as a steel hanger gave way and the other three holding up a 40-foot steel bar couldn't handle the extra weight.

There certainly is a design component to this - the mass of the concrete panels and the underdesigned '40-foot steel bar' that "couldn't handle the extra weight."

According to the Wikipedia article -

On July 12, 2006, investigators began questioning how the tunnel ceiling was constructed. The collapse of the ceiling structure began with the failure of a single steel hanger that held up the panels. The failure of that panel set off a chain reaction that caused other hangers to fail and sent 12 tons of concrete smashing below. Numerous problems with this same system of bolts and epoxy in the Ted Williams Tunnel were revealed by the state Office of the Inspector General in a 1998 report. Not only were the bolts too short, but the epoxy used to glue the bolts into the concrete was not up to standard. Safety inspections ordered in the wake of the tunnel collapse initially identified 60 potentially dangerous bolt fixtures that support the ceiling in the Interstate 90 connector tunnel. A follow-up investigation quadrupled the number of potentially dangerous bolt fixtures to 242.

That should have sent warning bells off. One has to ask why 'too-short bolts' were used? Who approved their use? Were they too short by design, or did someone use bolts, which were in violation of the drawings (the latter being criminal negligence or mischief)?

I can't believe they used poor quality concrete. Obviously when you're designing a concrete structure there's the question whether it'll be an "in situ" or premade structural members. If it's "in situ" the resistance between both the lab testtube concrete and the project's concrete mixed and then poured into its model to make the structural member will differ. Usually the later, has less resistance due to losses of water on hot temperatures. Mainly, there are methods to avoid much loss of resistance, but in some cases you might make concrete above the resistance for the design if you cannot control the losses of water.

According to Wikipedia the concrete's poor quality isn't connected to the leaks discovered in the tunnels. This may be the case, but it is well known that the temperature plays a role in the porosity of the concrete.

Staff: Mentor

Three of the bolts that were supposed to hold up the three-ton concrete panel that fell and killed a 38-year-old Jamaica Plain woman on Monday night have been found to have no epoxy on them, Attorney General Thomas F. Reilly said in an interview yesterday.

Reilly's investigation is focusing on whether the epoxy used in the tunnel failed , or if construction workers who installed the bolts misused or omitted the epoxy .

reeks of gross (criminal) negligence, by the construction workers and the construction managment/oversight.

Staff: Mentor

All Things Considered, July 10, 2007 · The National Transportation Safety Bureau laid blame Tuesday for last year's Big Dig ceiling collapse in Boston that killed a motorist.

Officials said the wrong epoxy was used to secure the ceiling panel, and pointed the finger at designers and inspectors who could have possibly prevented the tragedy.

What I heard was that the roof panels were increased in size, the number of bolts was reduced, and the expoxy used was inappropriate for that application. Nobody - not even one engineer - raised a concern or questioned the design.

This is negligence - and given that someone was killed - it's criminal negligence!

What I heard was that the roof panels were increased in size, the number of bolts was reduced, and the expoxy used was inappropriate for that application. Nobody - not even one engineer - raised a concern or questioned the design.

This is negligence - and given that someone was killed - it's criminal negligence!

Indeed it is. There will be some fallout to this. I guess it's unfortunate, but I would imagine the driving force behind the screw ups (the management) will go untouched while the lower level managers and workers will get hit with the consequences. I pitty any of the PEs on that job.